Hydrothermal Alkaline Treatment of PFAS Contaminated Water and Groundwater

Per-and polyfluoroalkyl substances (PFAS) have been used extensively since the 1940s due to their chemical stability and unique thermophysical properties. Those same properties make PFAS extremely recalcitrant environmental pollutants, and bioaccumulative toxins. Regulations are rapidly being established by U.S. states, including Michigan, New Hampshire, and New Jersey, beholding municipal water utilities to limit PFAS levels in drinking water to the low part-per-trillion (ppt) level. While several technologies exist for filtration of PFAS from water supplies, such as granulated activated carbon (GAC) and ion exchange resins (IXR), the end-of-life destruction of PFAS remains a challenge. The customer segment with the most pressing need for PFAS destruction services are project managers at environmental remediation consulting firms, who are required to manage end-of-life PFAS disposal for remediation of contaminated sites, and whose customers are increasingly seeking safe disposal solutions. Aquagga, in partnership with the University of Washington, is developing a continuous, field-deployable hydrothermal alkaline treatment (HALT) reactor for on-site disposal of PFAS-contaminated wet wastes and brines. The HALT process has been robustly demonstrated to facilitate complete defluorination of PFAS, in contrast to most other destructive technologies which only show partial PFAS destruction. Engineering efforts are needed to scale-up the process and deploy it for commercial use. Successful demonstration of the HALT process at realistic scale and throughput would provide an environmentally friendly alternative to incineration of PFAS-contaminated filter material and the disposal of PFAS•rich brines (such as AFFF).